1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * omap-pm-noop.c - OMAP power management interface - dummy version
  4 *
  5 * This code implements the OMAP power management interface to
  6 * drivers, CPUIdle, CPUFreq, and DSP Bridge.  It is strictly for
  7 * debug/demonstration use, as it does nothing but printk() whenever a
  8 * function is called (when DEBUG is defined, below)
  9 *
 10 * Copyright (C) 2008-2009 Texas Instruments, Inc.
 11 * Copyright (C) 2008-2009 Nokia Corporation
 12 * Paul Walmsley
 13 *
 14 * Interface developed by (in alphabetical order):
 15 * Karthik Dasu, Tony Lindgren, Rajendra Nayak, Sakari Poussa, Veeramanikandan
 16 * Raju, Anand Sawant, Igor Stoppa, Paul Walmsley, Richard Woodruff
 17 */
 18
 19#undef DEBUG
 20
 21#include <linux/init.h>
 22#include <linux/cpufreq.h>
 23#include <linux/device.h>
 24#include <linux/platform_device.h>
 25
 26#include "omap_device.h"
 27#include "omap-pm.h"
 28
 29static bool off_mode_enabled;
 30static int dummy_context_loss_counter;
 31
 32/*
 33 * Device-driver-originated constraints (via board-*.c files)
 34 */
 35
 36int omap_pm_set_max_mpu_wakeup_lat(struct device *dev, long t)
 37{
 38	if (!dev || t < -1) {
 39		WARN(1, "OMAP PM: %s: invalid parameter(s)", __func__);
 40		return -EINVAL;
 41	}
 42
 43	if (t == -1)
 44		pr_debug("OMAP PM: remove max MPU wakeup latency constraint: dev %s\n",
 45			 dev_name(dev));
 46	else
 47		pr_debug("OMAP PM: add max MPU wakeup latency constraint: dev %s, t = %ld usec\n",
 48			 dev_name(dev), t);
 49
 50	/*
 51	 * For current Linux, this needs to map the MPU to a
 52	 * powerdomain, then go through the list of current max lat
 53	 * constraints on the MPU and find the smallest.  If
 54	 * the latency constraint has changed, the code should
 55	 * recompute the state to enter for the next powerdomain
 56	 * state.
 57	 *
 58	 * TI CDP code can call constraint_set here.
 59	 */
 60
 61	return 0;
 62}
 63
 64int omap_pm_set_min_bus_tput(struct device *dev, u8 agent_id, unsigned long r)
 65{
 66	if (!dev || (agent_id != OCP_INITIATOR_AGENT &&
 67	    agent_id != OCP_TARGET_AGENT)) {
 68		WARN(1, "OMAP PM: %s: invalid parameter(s)", __func__);
 69		return -EINVAL;
 70	}
 71
 72	if (r == 0)
 73		pr_debug("OMAP PM: remove min bus tput constraint: dev %s for agent_id %d\n",
 74			 dev_name(dev), agent_id);
 75	else
 76		pr_debug("OMAP PM: add min bus tput constraint: dev %s for agent_id %d: rate %ld KiB\n",
 77			 dev_name(dev), agent_id, r);
 78
 79	/*
 80	 * This code should model the interconnect and compute the
 81	 * required clock frequency, convert that to a VDD2 OPP ID, then
 82	 * set the VDD2 OPP appropriately.
 83	 *
 84	 * TI CDP code can call constraint_set here on the VDD2 OPP.
 85	 */
 86
 87	return 0;
 88}
 89
 90/*
 91 * DSP Bridge-specific constraints
 92 */
 93
 94
 95/**
 96 * omap_pm_enable_off_mode - notify OMAP PM that off-mode is enabled
 97 *
 98 * Intended for use only by OMAP PM core code to notify this layer
 99 * that off mode has been enabled.
100 */
101void omap_pm_enable_off_mode(void)
102{
103	off_mode_enabled = true;
104}
105
106/**
107 * omap_pm_disable_off_mode - notify OMAP PM that off-mode is disabled
108 *
109 * Intended for use only by OMAP PM core code to notify this layer
110 * that off mode has been disabled.
111 */
112void omap_pm_disable_off_mode(void)
113{
114	off_mode_enabled = false;
115}
116
117/*
118 * Device context loss tracking
119 */
120
121#ifdef CONFIG_ARCH_OMAP2PLUS
122
123int omap_pm_get_dev_context_loss_count(struct device *dev)
124{
125	struct platform_device *pdev = to_platform_device(dev);
126	int count;
127
128	if (WARN_ON(!dev))
129		return -ENODEV;
130
131	if (dev->pm_domain == &omap_device_pm_domain) {
132		count = omap_device_get_context_loss_count(pdev);
133	} else {
134		WARN_ONCE(off_mode_enabled, "omap_pm: using dummy context loss counter; device %s should be converted to omap_device",
135			  dev_name(dev));
136
137		count = dummy_context_loss_counter;
138
139		if (off_mode_enabled) {
140			count++;
141			/*
142			 * Context loss count has to be a non-negative value.
143			 * Clear the sign bit to get a value range from 0 to
144			 * INT_MAX.
145			 */
146			count &= INT_MAX;
147			dummy_context_loss_counter = count;
148		}
149	}
150
151	pr_debug("OMAP PM: context loss count for dev %s = %d\n",
152		 dev_name(dev), count);
153
154	return count;
155}
156
157#else
158
159int omap_pm_get_dev_context_loss_count(struct device *dev)
160{
161	return dummy_context_loss_counter;
162}
163
164#endif
165
166/* Should be called before clk framework init */
167int __init omap_pm_if_early_init(void)
168{
169	return 0;
170}
171
172/* Must be called after clock framework is initialized */
173int __init omap_pm_if_init(void)
174{
175	return 0;
176}